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The cause of organ failure is enigmatic for many degenerative diseases, including end-stage liver disease. Here, using a C[Cl.sub.4]-induced rat model of irreversible and fatal hepatic failure, which also exhibits terminal changes in the extracellular matrix, we demonstrated that chronic injury stably reprograms the critical balance of transcription factors and that diseased and dedifferentiated cells can be returned to normal function by re-expression of critical transcription factors, a process similar to the type of reprogramming that induces somatic cells to become pluripotent or to change their cell lineage. Forced re-expression of the transcription factor HNF4α induced expression of the other hepatocyte-expressed transcription factors; restored functionality in terminally diseased hepatocytes isolated from C[Cl.sub.4]-treated rats; and rapidly reversed fatal liver failure in C[Cl.sub.4]-treated animals by restoring diseased hepatocytes rather than replacing them with new hepatocytes or stem cells. Together, the results of our study indicate that disruption of the transcription factor network and cellular dedifferentiation likely mediate terminal liver failure and suggest reinstatement of this network has therapeutic potential for correcting organ failure without cell replacement., Introduction Cirrhosis of the liver, the final pathway for liver injury from multiple types of insults, is a process that is difficult to manage and is responsible for 1.2% of [...]

Background: α1-antitrypsin deficiency is most commonly caused by a mutation in exon-7 of SERPINA1 (SA1-ATZ), resulting in hepatocellular accumulation of a misfolded variant (ATZ). Human SA1-ATZ-transgenic (PiZ) mice exhibit hepatocellular ATZ accumulation and liver fibrosis. We hypothesized that disrupting the SA1-ATZ transgene in PiZ mice by in vivo genome editing would confer a proliferative advantage to the genome-edited hepatocytes, enabling them to repopulate the liver. Methods: To create a targeted DNA break in exon-7 of the SA1-ATZ transgene, we generated 2 recombinant adeno-associated viruses (rAAV) expressing a zinc-finger nuclease pair (rAAV-ZFN), and another rAAV for gene correction by targeted insertion (rAAV-TI). PiZmice were injected i.v. with rAAV-TI alone or the rAAV-ZFNs at a low (7.5 x 1010vg/mouse, LD) or a high dose (1.5x1011vg/mouse, HD), with or without rAAV-TI. Two weeks and 6 months after treatment, livers were harvested for molecular, histological, and biochemical analyses. Results: Two weeks after treatment, deep sequencing of the hepatic SA1-ATZ transgene pool showed 6%±3% or 15%±4% nonhomologous end joining in mice receiving LD or HD rAAV-ZFN, respectively, which increased to 36%±12% and 36%±12%, respectively, 6 months after treatment. Two weeks postinjection of rAAV-TI with LD or HD of rAAV-ZFN, repair by targeted insertion occurred in 0.10%±0.09% and 0.25%±0.14% of SA1-ATZ transgenes, respectively, which increased to 5.2%±5.0% and 33%±13%, respectively, 6 months after treatment. Six months after rAAV-ZFN administration, there was a marked clearance of ATZ globules from hepatocytes, and resolution of liver fibrosis, along with reduction of hepatic TAZ/WWTR1, hedgehog ligands, Gli2, a TIMP, and collagen content. Conclusions: ZFN-mediated SA1-ATZ transgene disruption provides a proliferative advantage to ATZ-depleted hepatocytes, enabling them to repopulate the liver and reverse hepatic fibrosis. [ABSTRACT FROM AUTHOR]

α1-Antitrypsin deficiency is an inherited condition that causes liver disease and emphysema. The normal function of this protein, which is synthesized by the liver, is to inhibit neutrophil elastase, a [...]

Objective. Transplantation of isolated hepatocytes in animal models has been shown to correct inborn errors of metabolism. Based on these studies and our experience with hepatocyte transplantation in a child with Crigler-Najjar syndrome, isolated hepatocyte transplantation was performed to attempt metabolic reconstitution in a male infant with severe ornithine transcarbamylase (OTC) deficiency. Methods. An infant with an antenatal diagnosis of OTC deficiency was managed intensively to prevent hyperammonemia. Isolated hepatocytes were obtained by collagenase perfusion of donated livers not used for transplantation. Hepatocytes were infused in batches over the first 4 weeks of life via an umbilical venous catheter positioned in the portal vein. Immunosuppression consisted of tacrolimus and corticosteroids. Results. Over 4 billion viable hepatocytes were transplanted during the first 3.5 weeks of life. A period of metabolic stability was achieved between days 20 and 31 during which normal protein intake was tolerated while phenylbutyrate was weaned. During this time, plasma ammonia and glutamine remained within normal limits. Hyperammonemia reappeared abruptly on day 31 of life. Protein tolerance diminished to baseline; metabolic stability was subsequently reattained only following successful liver transplantation at 6 months of age. Conclusions. Isolated hepatocyte transplantation appeared to result in temporary relief of hyperammonemia and protein intolerance attributable to OTC deficiency. The metabolic stability achieved was lost after 11 days presumably because of rejection of the transplanted cells because of insufficient immunosuppression. Future attempts at isolated hepatocyte transplantation for inborn errors of metabolism in humans should include adequate immunosuppression and a liver biopsy as a means of proving hepatocyte engraftment and function. Pediatrics 2003;111:1262-1267; hepatocyte transplantation, infant, ornthine transcarbamylase deficiency, urea cycle disorder., ABBREVIATIONS. OTC, ornithine transcarbamylase; DV, ductus venosus; OLT, orthotopic liver transplantation; IV, intravenous. Isolated hepatocyte transplantation has been shown to be effective in restoring biochemical function in animal models of [...]

Transplantation of liver cells may be a promising treatment for Crigler-Najjar syndrome type 1. This disease is caused by a defect in the enzyme that metabolizes bilirubin, a chemical produced by the body. Researchers transplanted liver cells taken from a deceased boy into a 10-year-old girl with this disorder. About one month after the transplant, the level of bilirubin in her blood dropped to half its pre-transplant level. She also had enzyme activity and evidence that the bilirubin was being metabolized. Her transplanted cells lasted for more than 11 months.

Intestinal transplantation, in some cases combined with liver transplantation, may be an effective means of treating children with gastrointestinal disease who need an alternative to long-term intravenous feeding. Researchers performed 16 intestinal transplants, 13 of which were combined with liver transplants due to liver damage caused by intravenous feeding. Most children treated were under 5 years old, and most suffered from short bowel syndrome. The survival rate in the liver and intestine transplant recipients was 76% after an average follow up of 263 days, and 6 of the children no longer needed total intravenous feeding. Graft survival in these children was 61%. All three intestinal transplant recipients were alive after an average follow up of 384 days, their grafts were not removed, and they no longer needed intravenous feeding. The most significant complications were from infections and graft rejection., Objective. This report discusses the preliminary experience with intestinal transplantation in children at the University of Nebraska Medical Center. Patients. During the past 4 years, 16 intestinal transplants have been performed in infants and children. Thirteen have been combined liver and bowel transplants, and the remainder were isolated intestinal transplants. Nearly half of the patients were younger than I year of age at the time of surgery, and the vast majority were younger than 5 years of age. All but one had short bowel syndrome. Results. The 1-year actuarial patient and graft survival rates for recipients of liver and small bowel transplants were 76% and 61%, respectively. Eight of 13 patients who received liver and small bowel transplants remain alive at the time of this writing, with a mean length of follow-up of 263 (range, 7 to 1223) days. Six patients are currently free of total parenteral nutrition. All three patients receiving isolated intestinal transplants are alive and free of parenteral nutrition. The mean length of follow-up is 384 (range, 330 to 450) days. Major complications have included severe infections and rejection. Lymphoproliferative disease, graft-versus-host disease, and chylous ascites have not been major problems. Conclusions. Although intestinal transplantation is in its infancy, these preliminary results suggest combined liver and bowel transplants and isolated intestinal transplantation may be viable options for some patients with intestinal failure caused by short bowel syndrome or other gastrointestinal disease in whom long-term total parenteral nutrition is not an attractive option. Pediatrics 1996;97:443-448; short bowel syndrome, intestinal transplantation., Long-term home parenteral nutrition has been the mainstay of therapy for patients with intestinal failure caused by short bowel syndrome and other chronic intestinal disorders. Although this form of therapy [...]